SHARE-BASED COMPENSATION PLANS

3 Months Ended

Mar. 31, 2023

Share-Based Payment Arrangement [Abstract]

Share-Based Compensation Plans

The Company has five share-based compensation plans, including the 2019 Equity Incentive Plan (the “2019 Plan”), which was adopted in June 2019. Each plan authorizes the granting of shares of common stock and/or options to purchase common stock to employees and directors of the Company, as well as non-employee consultants, and allows the holder of the option to purchase common stock at a stated exercise price. The only plan under which the Company may currently grant equity awards is the 2019 Equity Incentive Plan although there remain outstanding awards under the other four plans. Options vest according to the terms of the grant, which may be immediately or based on the passage of time, generally over two to four years, and have a term of up to 10 years. Unexercised stock options terminate on the expiration date of the grant. The Company recognizes the share-based compensation expense over the requisite service period of the individual grantees, which generally equals the vesting period.

Share-Based Compensation Expense

Share-based compensation expense by classification for the three months ended March 31, 2023 and 2022 are as follows:


	Three Months Ended
(in thousands)	March 31, 2023		March 31, 2022
Research and development	$	217	$	294
General and administrative	342		305
Total	$	559	$	599

At March 31, 2023, total compensation cost not yet recognized was $1.9 million and the weighted-average period over which this amount is expected to be recognized is 1.4 years.